This application claims priority of Taiwanese Application No. 90221093, filed on Dec. 4, 2001.
1. Field of the Invention
This invention relates to a wood planing machine, and more particularly to a wood planing machine, which includes an angle-adjusting device that can adjust the angle of a workpiece-guiding plate with respect to a machine bed.
2. Description of the Related Art
Referring to FIGS. 1, 2, 3, and 4, a conventional wood planing machine 10 is shown to include a machine frame 11, a support member 12, an elongated cutter 13, a machine bed consisting of a right half 14 and a left half 15, and a workpiece-guiding plate 16. The support member 12 is disposed on a top surface of the machine frame 11. The cutter 13 is journalled on the support member 12 between the right and left halves 14, 15, and is rotatable by a driving source (not shown). The plate 16 is disposed on the right and left halves 14, 15 of the machine bed. A workpiece (not shown), which abuts against the plate 16, can be pushed along the latter on the machine bed from the right half 14 to the left half 15, and vice versa, so as to be cut by the cutter 13. An angle-adjusting device 20 is disposed to adjust the angle of the plate 16 with respect to the machine bed, and includes a fixed base 21, a movable seat 22, a rotatable member 23, a bearing member 24, a first control unit 25, a second control unit 26, and a guiding rail 27 that is bolted onto a horizontal top wall of the base 21 and that extends in a transverse direction of the machine bed. The base 21 is bolted onto a rear side wall 151 of the left half 15. The seat 22 has a bottom surface, which is formed with a slide slot 2221 that engages the guiding rail 27 so as to permit movement of the seat 22 on the base 21 in the transverse direction of the machine bed. The rotatable member 23 is bolted onto a rear surface of the plate 16. The bearing member 24 is unitary, and has a vertical rib 241 that is received slidably within an open-ended vertical slot 2211 in a vertical wall 221 of the seat 22, and a curved concave portion 242 that engages fittingly a curved convex portion 231 of the rotatable member 23. The second control unit 26 includes a locking element 261, a guide rod 262 that is journalled within a hole 2222 in a horizontal plate 222 of the seat 22, a nut 263, and a rotary lever 264 that is connected fixedly to the guide rod 262. The guide rod 262 extends through a vertical slot 2212 in the vertical wall 221 of the seat 22, a hole 243 in the bearing member 24, and a slide slot 232 in the convex portion 231 of the rotatable member 23, and has a threaded end that engages a threaded hole (not shown) in the locking element 261. The locking element 261 has a portion that is received movably within the slide slot 232 so as to prevent rotation of the locking element 261 on the guide rod 262. As such, the rotatable member 23 and the bearing member 24 are retained on the guide rod 262, and are confined between the locking element 261 and the nut 263. The rotary lever 264 is rotatable to move the locking element 261 on the guide rod 262 between a locking position, where the locking element 261 presses the rotatable member 23 and the bearing member 24 against the nut 263 so as to lock the rotatable member 23 on the bearing member 24, and a release position, where the rotatable member 23 and the bearing member 24 are unlocked from the locking element 261 so that the rotatable member 23 can rotate relative to the bearing member 24 for angle adjustment of the plate 16. The first control unit 25 includes a rotating shaft 251 with an eccentric pin 2511, a vertical bolt 252, a nut 253, and a rotary lever 254. The rotating shaft 251 is journalled within the seat 22. The eccentric pin 2511 extends into a hole 2521 in a head of the bolt 252 so as to move the bolt 252 vertically relative to the base 21. The bolt 252 extends through a guide slot 212 in a horizontal top wall 211 of the base 21, which extends in the transverse direction of the machine bed. The nut 253 is disposed under the top wall 211 of the base 21, and engages the bolt 252. The rotary lever 254 is connected fixedly to the rotating shaft 251, and is rotatable to move the bolt 252 between a locking position shown in Fig. 4, where the nut 253 presses against the top wall 211 so as to lock the seat 22 on the base 21, and a release position, where the nut 253 is spaced apart from the top wall 211 so as to release the seat 22 from the base 21, thereby permitting position adjustment of the plate 16.
The aforesaid conventional wood planing machine 10 suffers from the following disadvantages:
(1) Because the clamping force of the locking element 261 and the nut 263 acting on the rotatable member 23 and the bearing member 24 is relatively small, the plate 16 cannot be fixed effectively on the machine bed during operation.
(2) Because the plate 16 is supported directly by only one element, i.e. the rotatable member 23, the former sways easily about the latter during operation.
(3) To adjust accurately the angle of the plate 16 with respect to the machine bed, there is a need for a relatively high manufacturing precision of the convex portion 231 of the rotatable member 23 and the concave portion 241 of the bearing member 24.
(4) The seat 22 is guided to move on the base 21 in the transverse direction of the machine bed by engagement of the guiding rail 27 and the slide slot 2221 in the seat 22, thereby hindering smooth movement of the seat 22 and the plate 16.
An object of this invention is to provide a wood planing machine, which includes a workpiece-guiding plate that can be fixed effectively relative to a machine bed during operation.
Another object of this invention is to provide a wood planing machine, which does not require a high manufacturing precision of a device for supporting rotatably a workpiece-guiding plate.
Still another object of this invention is to provide a wood planing machine, which includes a movable seat that can move smoothly on a fixed base.
According to this invention, a wood planing machine includes a workpiece-guiding plate disposed on a machine bed, a base disposed fixedly on the bed, and a seat disposed movably on the base. Two fixing blocks are disposed fixedly on two opposite sides of the seat. Two coupling blocks are disposed fixedly on the plate. Two links are connected pivotally to the fixing blocks and the coupling blocks so as to permit rotation of the coupling blocks relative to the fixing blocks such that the angle of the plate can be adjusted with respect to the bed. A control rod assembly extends through the first and second links, and is rotatable to move the first and second links toward each other so as to clamp the fixing blocks and the coupling blocks, thereby locking the plate on the bed. Because the plate is connected to the seat by the links, which are disposed on the two sides of the seat, the plate can be fixed effectively relative to the seat. Furthermore, the plate can be prevented by the links from swaying about the seat during operation. In addition, there is no need for a high manufacturing precision for the links, the fixing blocks, and the coupling blocks.
Preferably, the seat is generally inverted U-shaped, and has a horizontal top wall and a pair of first and second side walls that extend integrally and downwardly from two opposite sides of the top wall and that define a dovetail groove therebetween under the top wall. The base has a fixed dovetail rib that is inserted into the dovetail groove and that presses against the first side wall, and a movable dovetail member that is inserted into the dovetail groove and that is movable between a locking position, where the dovetail member presses against the second side wall so as to lock the seat on the base, and a release position, where the dovetail member is spaced apart from the second side wall so as to permit movement of the seat relative to the base. Accordingly, the seat can be locked firmly on the base. Furthermore, because the dovetail rib and the dovetail member are disposed within two opposite sides of the dovetail groove, the seat can be guided to move smoothly on the base.